SOUTH BEND, Ind.—Notre Dame defensive end Stephon Tuitt is ready to do his best impersonation of nose guard Louis Nix III.

No, the 6-foot-6, 322-pound junior from Monroe, Ga., isn’t trying to take the place of Nix as the team’s most entertaining interview. Tuitt is quiet and appears uncomfortable talking with the media.

Tuitt is at home anywhere on the defensive line, though, whether he is getting after quarterbacks from his usual position at defensive end or moving inside against the option to clog things up in the middle for Notre Dame (5-2) against Air Force (1-6) with Nix not making the trip after not practicing all week because of knee tendinitis.

That’s fine with Tuitt.

“My job is to be in the middle, to be a Louis Nix,” he said.

Tuitt has shown he can be disruptive against option teams. He had four tackles, including two for losses, and a 77-yard fumble return for a touchdown in the season-opener against Navy in 2012. As a freshman a year earlier, Tuitt had seven tackles and two quarterback hurries against Navy and five tackles against Air Force. Tuitt said he played against a lot option teams in high school.

“So I’m a little more comfortable than some of the members on our team who didn’t go against the option as much,” he said.

Another concern for Air Force is that Tuitt is finally healthy. Through six games last season, Tuitt had 28 tackles, including 8.5 sacks. But he was slowed by a sports hernia in the second half of the season, finishing with 47 tackles, including 12 sacks. That was just shy of the school record of 13.5 set by Justin Tuck in 2003.

Tuitt underwent surgery in the spring for the sports hernia. After Tuitt showed up noticeably heavier in August there was speculation that perhaps he had let reports he might be an NFL first-round draft pick go to his head and hadn’t put in the work during the offseason. Tuitt would not discuss the weight gain.

Kelly later explained that Tuitt had added weight because he had been unable to do certain exercises for nearly four months after the surgery.

“It wasn’t because he decided to eat Cheetos on the couch and not work out. He had to do a different work out,” Kelly said.

Kelly said earlier this month that Tuitt was still feeling the effects of the surgery, saying it had affected his back, hip flexors and “a lot of things.”

Through three games, Tuitt had just four tackles and one sack. In the next three games, he had 14 tackles and two sacks. After a week off, Tuitt had a career-high seven tackles, two sacks, a pass breakup and two quarterback hurries against USC last week and said he is finally feeling healthy.

“It was a challenge because I had to get everything back, get everything back strong again,” he said. “But right now, I’m better than ever. My game is coming all together.”

Kelly called Tuitt’s performance against USC “dominating.”

“He’s played himself into the kind of condition and shape necessary for him to exert his physical prowess on the football field,” he said.

Tuitt knows he can play better.

“When you watch the game as a person you say, ‘Oh I made plays.’ But when you go back and watch film, and I look at the plays I could have made, and probably made more, those are things I look at,” he said.

Tuitt is a lot more comfortable talking about defending the option than discussing his options of staying in school or entering the NFL draft. Tuitt caused a stir last week when he told the Notre Dame student newspaper that he planned to return for his senior season

Tuitt said he misspoke, saying he answered without thinking about what he was saying. He said he hasn’t decided what he will do next season.

“It’s something I have to talk about with coach Kelly and my mom. It’s something I pray about,” he said. “Right now I’m focused on every week.”

This week he’s focused on being Louis Nix.

NOTES: Right guard Christian Lombard, a two-year starter, had season-ending Wednesday to repair a herniated disk, Kelly said. Freshman Steve Elmer will take over as the starting right guard. … Kelly says quarterback Tommy Rees, who missed most of the second half against USC with a neck injury, looked good in practice all week.